public static uint[] GetPath(DijkstraAlgoData dad)
{
var count_walker = dad.prev_node[dad.ending_node];
int count = 0;
while (count_walker != INVALID_NODE)
{
count += 1;
count_walker = dad.prev_node[count_walker];
}
if (count == 0)
{
return(null);
}
else
{
var ret = new uint[count];
int i = 1;
var path_walker = dad.ending_node;
while (path_walker != dad.starting_node) // i <= count
{
ret[count - i] = path_walker;
i += 1;
path_walker = dad.prev_node[path_walker];
}
return(ret);
}
}
public static DijkstraAlgoData StartDijkstra(DijkstraGraph graph, uint starting_node, uint ending_node)
{
var dad = new DijkstraAlgoData();
dad.graph = graph;
dad.starting_node = starting_node;
dad.ending_node = ending_node;
dad.node_cost = new uint[graph.nodes.Length];
dad.prev_node = new uint[graph.nodes.Length];
for (int i = 0; i < graph.nodes.Length; ++i)
{
dad.node_cost[i] = 1000000000;
dad.prev_node[i] = INVALID_NODE;
}
dad.node_cost[starting_node] = 0;
dad.open_list = new uint[graph.nodes.Length];
dad.open_list[0] = starting_node;
dad.open_list_size = 1;
return(dad);
}
public static bool Process(DijkstraAlgoData dad)
{
var node = dad.open_list[dad.open_list_size - 1];
dad.open_list_size -= 1;
for (int i = 0; i < dad.graph.edges.Length; i += 3)
{
var edge_start = dad.graph.edges[i];
var edge_end = dad.graph.edges[i + 1];
var cost = dad.graph.edges[i + 2];
if (edge_end == node)
{
var v = edge_start;
edge_start = edge_end;
edge_end = v;
}
if (edge_start == node)
{
if (dad.node_cost[edge_end] > (dad.node_cost[node] + cost))
{
dad.node_cost[edge_end] = (dad.node_cost[node] + cost);
dad.prev_node[edge_end] = node;
dad.open_list[dad.open_list_size] = edge_end;
dad.open_list_size += 1;
}
}
}
if (dad.open_list_size == 0)
{
return(true);
}
else
{
return(false);
}
}
